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Division Spotlight
Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
Meeting Spotlight
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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ANS standard updated for determining meteorological information at nuclear facilities
Following approval in October from the American National Standards Institute, ANSI/ANS-3.11-2024, Determining Meteorological Information at Nuclear Facilities, was published in late November. This standard provides criteria for gathering, assembling, processing, storing, and disseminating meteorological information at commercial nuclear power plants, U.S. Department of Energy/National Nuclear Security Administration nuclear facilities, and other national or international nuclear facilities.
Scott D. Ramsey, Gregory J. Hutchens
Nuclear Science and Engineering | Volume 168 | Number 3 | July 2011 | Pages 265-277
Technical Paper | doi.org/10.13182/NSE10-11
Articles are hosted by Taylor and Francis Online.
The utility of stochastic point kinetics theory has been demonstrated through the examination of a criticality excursion in a supercritical system. It has been found that a deterministic point kinetics model underpredicts the excursion maximum energy release by up to two orders of magnitude with respect to a counterpart stochastic model. This potentially large underprediction shows that neutron population fluctuations play an important role in the evolution of that system. This work provides a review of the formalism and approximations used to arrive at this conclusion. To broaden the result's applicability, we relax several approximations, leading to the construction of new, nonanalytical expressions. We compare the two sets of results using local sensitivity analysis, which also allows us to assess the impact of potential uncertainties in included model parameters or data. This comparison (presented also for a 235U system) also proves useful in assessing the validity of the approximations under consideration.